Have you guys heard of "Spaghetti noodle effect"

Beginner and pro baristas share tips and tricks.
coffee_plXR

#1: Post by coffee_plXR »

Hi guys,

Is it very common that shot time gets longer in cold start?
(I use LaCimbali M39 GT, Fiorenzato 84mm)
Normally, It used to be nice & smooth during daytime but severely disrupted when I just turn on the machine starting extraction set-up.

While looking for more research I found somebody saying that this is called "Spaghetti noodle effect"
Just like when you cut cold dry noodle, it has more crisp(small particle), Cooked hot spaghetti just cut off easily without particle.

Likewise, coffee has much small particles when ground in cold, particles reduced when heated properly.

I want more scientific data on this phenomenon.

Always welcome your ideas & opinion!
Thanks!

Irishespresso

#2: Post by Irishespresso »

Are you talking about temperature of beans when you grind them or water temperature when you brew espresso? Kind of hard to tell from your post since you liken grinding the beans to cutting both raw and cooked spaghetti.

Assuming you're talking about brew water temp, there is no secret that water is a more effective solvent as the temp increases, therefore extracting more from the ground coffee.

If you're talking about temp of beans while they're ground, I'd imagine that if they're frozen, they may fracture into smaller pieces more readily, and while warm they'd in theory do so less, but I don't know enough to speculate on whether it would be noticeable in the temp ranges we're talking about.

The difference in how a raw piece of spaghetti cuts vs a cooked one is likely more a function of water content than temp. Take a cold, cooked piece of spaghetti out of the fridge and you'll see it cuts as cleanly as one that is fresh out of the pot. Contrarily, put a raw piece in a hot oven for 10 minutes and you'll likely find it fractures similarly to a cold, raw piece fresh out of the box. Taken to extremes, even cooked spaghetti at very low temperatures will fracture as the water contained in the noodle will have frozen and the noodles will therefore be brittle.

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coffee_plXR (original poster)

#3: Post by coffee_plXR (original poster) »

Thanks :)
I suppose your 3rd paragraph can be the answer.

I'd say the water temperature no matters because machine water is always stable.

By the way, can I find more details on that bean temperature affects ground particles? I need backgrounds.

Jeff
Team HB

#4: Post by Jeff »

You may be significantly underestimating the time it takes a machine, especially a commercial machine, to reach temperature stability. Just because the digital display says "201" or "94" doesn't mean that will be your brew temperature as it heats up. The boiler reaching temperature does not mean that the machine is ready to brew at that temperature.

mathof

#5: Post by mathof »

coffee_plXR wrote:By the way, can I find more details on that bean temperature affects ground particles? I need backgrounds.
There's this:

https://www.nature.com/articles/srep24483

coffee_plXR (original poster)

#6: Post by coffee_plXR (original poster) »

Oh my gosh, you are awesome! this is a great one! Thanks:)